Iunicipal telegraph



(No Model.)

' M. MARTIN.

MUNICIPAL TELEGRAPH.

No. 375,299. Patented Dec. 20, 1887-.

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. UNITED STATES PATENT OFFICE.

MORRIS MARTIN, OF MALDEN, MASSACHUSETTS, ASSIGNOR TO THE MUN ICI- PAL SIGNAL GOMPANY, OF PORTSMOUTH, NEW HAMPSHIRE.

MUNICIPAL TELEGRAPH.

SPECIFICATION forming part of Letters Patent No. 375,299, dated December 20, 1887.

Serial No. 207,167. (No model.)

' I citizens when required.

The invention consists in various appliances and combinations of instruments and circuits by which these various operations are effected.

In the accompanying drawings, illustrating my invention, Figure 1 is a front elevation of a signal-box. forming part of an apparatus embodying this invention, parts being broken away to show other parts; Fig. 2. a partial vertical section thereof on line a: :10, Fig. 1; Fig.

3, a detail'of the mechanism for indicating the number of the citizens key by which the box has been operated; Fig. 4, a detail of the mech anism of the pull operated by the key, and Fig. 5 a diagram showing the circuits and ap- 0 paratus included therein.

The signal-transmitting device at the box (best shown in Fig. 2) consists of a train of wheel-work, a, actuated by a shaft, a, having a ratchet, a fixed thereon and acted upon by 5 a spring, (not shown,) tending to turn the ratchet in the direction of the arrow thereon, the said shaft being turned to wind the spring and bring the teeth of the ratchet into engagement with the pawl a on the main wheel of 0 the train a (which wheel is loose on the shaft a) by a crank, (0*, connected by a link, a,with a rocking lever or frame, a", supported on a rock-shaft parallel with the shafts of the train of wheel-work. Thus, by depressing the lever 5 a and then releasing it, the train is set in operation in substantially the same manner as in the well-known fire-alarm and districtsignaling apparatus, from-which the mechanism thus far described differs mainly in having a number of break-wheels, b, revolved simultaneously by the train, instead of a single wheel, as is usual in district-telegraph boxes.

The lever a is depressed and then-released to set the break-wheels b in rotation by any one of a series of pulls, 0, .consisting of finger- 5 pieces or handles connected with slide-bars d, having a longitudinal movement in guides e e, and each provided with a pawl, 61, which, when the said bar is moved down by its pull 13, engages a cross-bar or treadle, a connected with thelever a, depressing the said lever a sufficient distance to wind the spring, and then releasing it, owing to the fact that the treadle a moves in an arc, while the pawl moves in a straight path.

The slide-bars d are provided with lookingpins d cooperating with a locking device, f, shown as a plate extending across in front of all of the slide-bars and pivotally connected with the fram e-work of the motor at f. The said locking-bar f or its supporting-arm is provided with an arm,f engaged by a rod, f operated by a projection, a, from the winding-lever a", and as soon as the said lever is moved down by one of the slide-bars the rod f drops and the bar f tends by its weight to move inward toward the slide-bars d, and as soon as the slide-bar that is operated has been moved fully down the bar fwill move in above the pin d thereof, holding said pin down, and also obstructing the pins of the other pulls, so that they cannot be moved down until the winding-lever a returns to its normal position, when it will raise the rod f and the latter will move the locking-barfoutward,releas- 8 ing thepin d of the slide-bar that has been depressed,and permitting the same to be moved upward by a spring, d".

The slide-bars d are each provided'with a contact-spring, b, insulated from the frame- 0 work and normally held out of contact with the corresponding break-wheel Z), as shown in full lines. When, however, any one of the slide-bars is depressed, the corresponding spring is moved down into engagement with 5 the corresponding break-wheel, as shown in dotted lines, Fig. 2, and remains there during the transmission of a signal, while the bar is retained depressed by the locking device f. When in this position, the break-wheel spring b comes in contact with a spring, I), which completes the circuit controlled by the breakwheel that is in operation. The lever a is also provided with a contact-spring, I), which, when the said lever arrives at its normal position after the transmission of a signal, comes in contact with the spring If, for the purpose to be hereinafter described.

\Vhen it is desired to distinguish some of the signals from others before looking at the recorded message at the main oflice, the slidebars (7, co-operating with the brealrwheels by which messages requiring especial immediate attention are transmitted, act on a circuit-controlling device consisting of two springs, z" i, connected with one portion of the line, aml an intermediate spring, 5, connected with the other portion and acted upon by the slide-bar, which, when in its normal position, presses it against the upper spring, i, closing the circuit between them. \Vhen the bar is moved down, the spring follows it by its own elasticity, leaving the spring t, and thus breaking the circuit, but immediately afterward coming in contact with the spring 2', and thus closing the circuit, so that a momentary break is pro duced when the bar is depressed and before the signal is transmitted.

In addition to the transmitting mechanism just described, the box contains a polarized signalinginstrument, S, and another signaling-instrument or tap-bell, S, operated by a neutral magnet, the coils of which are of a considerable resistance, and preferably also contains a telephone, T, which may, however, be

omitted when the telegraphic messages alone are to be used. The relation and mode of operation of the devices thus far described may be best understood by referring to Fig.5,whieh shows the apparatus at one of the boxes and at the main office, it being understood that the circuit connecting the said devices passes g through any desired number of boxes, (indicated at A.)

The main batteryB, by the current of which the messages are transmitted, has its terminals 2 3 connected with a pole-changing device, P, which may consist of a cylinder or drum, 1), having contact-pieces pp", occupying opposite halves of its periphery and being connected with rings encircling the said drum, that are always in contact with springs connected with the battery-wires 2 3, so that one of the said contact-pieces, p, is always connected-with one pole, and the other contactpiece, 1)", with the other pole of the battery. The main line or circuit, including the various instruments, terminates in springs 19 1)", hearing on the drum in line with the contactpieces pp so that when the said drum revolves the connection of the poles of the battery with the line is reversed at each half-rotation of the drum, the operation of which is substantially the same as that of the commutator of Siemenss magneto-electric machine. The said drum 1) is acted on by a clock-work or motor, a portion only of which is shown,

provided with a detent, p, by which it may be stopped or set in motion, as desired, by the operator.

From the spring p co operating with the polechanger, the line is continued, as indicated at 4, to a receiving-relay, a, controlling a register, R, in the usual manner, the said relay being adjusted to respond to certain changes in current strength, as well as complete interruptions of the current. From the relay 1' the main line is continued at 5 to a relay, r, adjusted so as not to aifect the changes in current strength that operate the relay T, but only to a total interruption in the current. The said relay 0" controls a local circuit, 30, including an electro-magnet, m, the armature of which controls a circuit-closer, a, and when attracted closes a branch, 31, of the local circuit 30, including the battery and the said magnet m, which will thus be retained in circuit alter having been momentarily energized by the closing of the circuit 30 by the relay 1". The said magnet m forms part of an indicating instrument or alarm, S (shown as avibrating bell,) which is thus set in operation for an indefinite period of time through the action of a momentary interruption in the eurrent on the main circuit and relay 1".

The relays 1' T will not be affected by the reversal of polarity produced by the polechanger P, and, it'desired, they mightbe placed in the wires 2 or 3 between the battery and pole-changer, being shown external to the polechanger merely to avoid confusion.

The circuit is continued from the relay 1* by wire 6 out of the main ofiice to the ditlerent boxes, in each of which the line 6 entering is shown asconnected with one terminal of the telephone T, the other terminal of which is connected by wire 7 with one terminal of the magnet m of the signal S, the other terminal of which is connected by wire 8,which passes through the different circuit-controlling de vices t i i scriatim to one terminal of the polarized signalinstrument S, the other terminal of which is connected with the main line 9, leading out from the other side of the box, to the contact spring 1) oi the pole-changer at the main office. The telephone T is provided with a shunt controlled by its gravity'switeh, being closed when the said telephone is hung up, and the wire 7 at the one side of the magnet m is connected by wire 12 with the breakwheels I), and also with the winding-lever n. and spring I) thereon,while the contact-spring b is connected by wire 18 with the wire 8 at the other side of the magnet m and no1mally,wlie11 the box is not operating, the contact of the spring b with the spring I) closes the shunt 12 13, of low resistance, around the magnet on. \Vhen, however, a signal is to be transmitted and the winding-lever a is depressed, it opens the said shunt at b I)", but at the same time one of the springs l/is brought into contact with the co-operating break-wheel h, which thus controls the said shunt, opening and closing the same, and thus throwing the resistance of the message determined by the wheel b-that is thrown into operation will be transmitted. If needed, more resistance can be placed in the Wire 7 or 8 between the points where the shuntwires 12 13 join them. If the pull or slide bar 01, by which the box is operated,was one that cooperated with one of the circuit-controlling devices it" i a momentary break in the circuit would have been produced in the act of winding the box before the signal is transmitted, which break would cause the alarm-instrument S at the main office to be set in operation, as before described; but if no such interruption were produced the message would be merely transmitted to the register It without operating the signal S at the main office.

The polarized signal S at the box is provided with a shunt, 14: 15, of low resistanceincluding a circuit-breaker, t, which may be operated from the outside of the box, preferably by a button, t, that will be placed at a point where it will not be readily noticed except by the person instructed to use it, and the officer would be instructed to press this button upon arriving at a box. -If the attendant at the main office desires to communicate with an oflicer, the pole-changer P at the main office will be set in operation, and the next time that the officer arrives at a box and opens the circuit-closer t the signal S will be operated by the reversals in current produced by the polechanger I, and the officer will know that he is wanted and will open the box and transmit a signal to the main office that would be known as a call to the telephone.

The telephonecall may be produced by merely breaking the circuit, and thus setting the instrument S in operation, without producing any on the instrument R except a single dot or dash. The resistance of the magnet of the polarized signal S is intended to be insufficient to affect the relay r. When the signals are transmitted by the change in current strength, as described, and an additional alarm is produced by an interruption in the current, the apparatus may be used for transmitting patrol or on-duty signals, which will not be accompanied by the alarm, as they will usually be the most numerous signals, and do not require immediate attention at the main office, while all the other signals that do require immediate attention will be accompanied by the alarm, so that the attendant will immediately examine such signals to see whatis wanted and take the proper action.

The mechanism by which a citizen can transmit a call without opening the box and obtaining access to the pulls a is best shown in Figs. 1, 2, and 4. One of the slide-bars d, instead of being provided with a finger-piece,c, is connected by a link, a, with one arm of a lever, to, the other arm of which rests over an eccentric or cam, a (see Fig. 2,) on a shaft, a adapted to be operated by a key or wrench, K, inserted through a key-hole, K, in any convenient part of the box. The key preferably engages the shaft u at its end, either having a square portion which engages a corre sponding square socket or engaging like a screw-driver, so that it turns the shaft without the cooperation of the bit or usual projecting portion, k, of the key. By rotating the key and shaft and cam or eccentric a the end of the lever a connected with the slide-bar is depressed, operating the said slidebar to depress the winding-lever a and transmit a message in just the same manneras before described when referring to the slide-bars operated by the finger-pulls c.

In order to place a check upon careless or unnecessary use of the keys K, which are intended to be distributed among responsible citizens, the bit portions of said keys are all different, and the keys are numbered to 'correspond with the shape of their bits, and when delivered to a citizen the number of the key is registered, together with the citizen-s name. The said bits k are like those of the keys of an ordinary tnmbler-1ock and co-operate with a series of pivoted levers or pointers, 70 It" It, the ends of which extend over a graduated numbered segment or'dial, K", Fig. 1. Thus, when the key is revolved to turn the shaft a and send an alarm, the bit also raises the said pointers different heights, according to the length of difierent portions of the key-bit, placing the ends of said pointers opposite different figures on the segment K, making a combination of figures the same as the number of the key. In order to retain the pointers opposite the figures to which they are thus set,the said levers are provided with segmental ratehets k co-operating with pawls e, which retain them at the height to which they were raised by the key.

In order to prevent error, which might arise in case two persons should separately operate by keys before the first message was answered, a tripping device is preferably provided for the said pawls, shown as a lever, 70, pivoted concentrically with the pawls and provided with a pin that extends under shoulders on the pawls k, as shown in Fig. 3, so that when the said arm k is raised the pawls It will be turned back and thrown out from the teeth of the ratchets, and each key is provided with an auxiliary bit or projection, k,(see Fig. 2,) that engages the said tripping-lever k and lifts the same, and then releases it before the bit It arrives at and operates upon the indicatinglevers 7c 70 It, so that each key will destroy the combination last made and leave its own combination of figures indicated by the pointers.

The officer on arriving at the box will, if it IlO by raising the disengaging-leverk or tripping the pawls k by hand. As it may sometimes be desirable for officers to transmit a call without opening the box, they may also be provided with keys like the one K, except that they will have neither of the bits or k", and will thus turn the shaftu and operate the pull without, however, producing any effect on the indicating-levers.

\Vhen desired, the apparatus may be used without providing for a patrol or on-duty signal to be operated at stated intervals by the oifieer on his beat, since, owing to the signal S, the officer would be obliged to visit the boxes regularly, as he knows that a signal may at any time be waiting for him, and that he will be called to account for failure to respond to said signal within a reasonable time. In this method of operation the apparatus could be simplified, as the signal S at the:box might be omitted. as well as the circuit controlling devices i I? 2", and the signals may be transmitted by breaking and closing the circuit in the usual manner. It is preferable, however, to transmit the signals by changes in current strength, as they would then not interfere seriously with the operation of the telephone, and the momentary break produced by the devices 1? i i would be scarcely perceptible. If desired, the button t might be inaccessible, except by a suitable key or instrument carried by the ofticer, which might be the same key by which he can operate the shaft a. By making the resistance that is used to vary the current strength at the signal-box for giving signalsas the coils of a tap-bellthe said bell will operate while the signals are being transmitted, and thus show whether or not the circuit is in working order, and by opening the shunt 12 13 for the said tapbell it may be used to respond to breaks in the circuit produced at any other point, thus providing for telegraphing messages between the different stations by means of eircuit-breaking keys, such as usually provided in fire-alarm boxes. Such telegraphic messages may be received at the main office on the register R like the regular automatic messages.

I am aware that is not new to provide a telegraph signal-box with a signal controlled at the main ofiice orsignal-receiving station, and also that it is not new to have a signal at one station controlled as to its indication from another station, but called into operation by the person at the station where said signal is lo cated, so that the person calling it into operation can discover the intent of the person at the other station having control of the indication of said signal, such an apparatus being shown, for instance, in Patent No. 289,83i, dated December 11, 1883. The apparatus of said patent, however, differs from that of the present application in that the transmitter at the remote station, though controlled, as to the signal it will transmit, by the operator at that station, is set in operation by the person at the station where its signal is to be received, the

receivirig-instrument being always in condition to respond to the transmitter if operated, while in the present apparatus the operation of the transmitter is controlled by the person at the station of the transmitter, and the signalreceiving instrument is normally unafi'ected, but called into operation when desired by the person who is to receive the signal.

In another application, Serial No. 209,661, filed July31, 1886, Ihave shown and described a signal-box having but one break-wheel and a motor therefor, with the winding device of said motor, and an actuator for said winding device, and a locking device for said actuator, by which it is retained inoperative after the motor is wound until the motor is run down and a message transmitted; and I do not in the present application broadly clai in the combination of the winding device, actuator, and locking device, the present application being limited in this particular to the arrangement in which more than one actuator is employed for the motor, which is adapted to transmit more than one message, and the locking device cooperates with all the actuators, and being limited so far as a single actuator is conccrned to the construction in which the contact-spring of the break-wheel is connected and movable with the said actuator.

I claim- 1. In a signal-box, a motor and break-wheel actuated thereby, combined with a pull or winding device for said motor and contactspring for said break-wheel connected with said pull, and a locking device by which the said pull, when moved to wind the motor, is retained in position with the contact-spring on the break-wheel during the operation of the motor, substantially as described.

2. In a signal-box, a motor and series of break-wheels operated simultaneously thereby, combined with a series of pulls for winding the said motor, each corresponding to one of said break-wheels, and a locking device controlled by the said motor, by means of which the pulls are all rendered inoperative after one has been operated until the signal is complete] y transmitted,substantially as described.

8. In a municipal-telegraph apparatus, a pole-changer and motor therefor at the main office, by which the line-current may be continually reversed, combined with a signal-box and circuit connecting the same with the main office and a polarized signalinginstrument 7 in the said box, and a normally-closed shunt of low resistance around said instrument and circuit breaker therein, whereby the said shunt may be opened and cause the signal to indicate whether or not the pole-changer at the main office is in operation, substantially as and for the purpose described.

4. A signal-box and a signaltransmitting device therein, and a pull for operating the said transmitter, the said pull being arranged to be operated by a key from the outside of the box, combined with a series of indicatingpointers operated by the key and making an indication corresponding to the shape of the key, substantially as and for the purpose described. v

5. A signal-box and signal-transmitting device therein adapted to be operated by a key from the outside of the box, combined with a series of indicatingpointers operated by the said key, and pawls co-operating with the said pointers to retain them in the position to which they were moved by the key last operated, and a tripping device for said pawls operated by the key before it operates the indicating-pointers, substantially as and for the purpose described. r

6. The combination, with a key, of an indicating-pointer actuated by the said key and means for retaining it in the position in which it is left by the key, for the purpose of making an indication corresponding to the size or shape of the part of the key acting upon it,

I substantially as described.

7 A signal-box, a sig flal'transmitter and motor therein, and a starting-lever, combined with an indicating-pointer and means for retaining the indicating-pointer in any position that it may be moved, and a key for simultaneously moving the indicating-pointer and startinglever, substantially as described.

8. A signal-box containing a signal-transmitter and motor therefor adapted to be set in operation by one of several signal-transmitting dissimilar keys inserted through a key-hole in the box and thereafter removed, combined with a local detector to detect at the box which one of the several removable signal-transmitting keys has been used to transmit the signal, the key itself forming a co-operativepart of said detector, while the other 00- operative part thereof is concealed within the box, substantially as described.

9. A telegraph apparatus comprising a signal-box or out-station and main ofiice or receiving-station connected in circuit therewith containingthe following instrumentalities: a tap-bell at the box and a break-wheel controlling a shunt or circuit of low resistance around the said tap-bell, and a receiving-instrument at the main office adjusted to operate by the changes in current strength produced by the introduction and removal of the resistance of the tap-bell at the box by the break-wheel,

the said tap-bell responding to the action of the break-wheel when the circuit is in oper-' ative condition, the signals being normally transmitted without opening the circuit, substantially as described.

In testimony whereof I have signed my name to this specification in the presence of two subscribing witnesses.

MORRIS MARTIN. 

